1. Field of the Invention
The present invention relates to a slide type portable terminal, and more particularly, to a slide type portable terminal in which a slide unit and a main unit can be slid against each other.
2. Background of the Related Art
As examples of a portable terminal, there are a mobile phone whose main function is a telephone function, a PDA (personal digital assistant) whose main function is an electronic note, a smart phone having a combined telephone and electronic note function, and the like. Such a portable terminal can be classified into bar type, flip type, folder type and the like according to an external configuration thereof.
Recently, a slide type portable terminal has come into the market. A configuration of a related art slide type portable terminal is illustrated in FIGS. 1 and 2.
As shown in FIGS. 1 and 2, the slide type portable terminal includes a flat, plate-shaped main unit 1 and slide unit 5 that are coupled to be slid along a longitudinal direction. A display screen 2 is provided on a front surface of the main unit 1. A variety of information is displayed on the display screen 2. A speaker 3 is also provided on an upper end of the front surface of the main unit 1 adjacent to the display screen 2. Further, a plurality of function buttons 4 are provided on a lower end of the front surface of the main unit 1.
The slide unit 5 can be slid against the main unit 1 to protrude beyond the main unit 1 at a predetermined distance and is provided with a plurality of number buttons 6 at a front surface thereof The number buttons 6 are fully exposed to the outside when the slide unit 2 is slid against and protrudes beyond the main unit 1. However, the number buttons 6 are covered with the main unit 1 when the slide unit 5 and the main unit 1 overlap each other. Further, a microphone 7 is provided on a lower end of the front surface of the slide unit 5.
FIG. 2 shows a structure for providing the sliding operation of the main unit 1 and slide unit 5 with respect to each other. In such a case, a main plate 10 and a slide plate 15 serve as the sliding structure. The main plate 10 is fixed to the main unit 1 and the slide plate 15 is fixed to the slide unit 5.
Guide channels 11 are formed on both lateral sides of the main plate 10 in a longitudinal direction. Further, fixing holes 12 are bored through lateral ends of the main plate 10. The fixing holes 12 are portions into which an end of a torsion spring 19 are fixed.
The slide plate 15 is relatively shorter than the main plate 10. Further, guide ribs 16 are formed at both lateral ends, respectively, such that the slide plate 15 can be guided and slid along the guide channels 11. Fixing holes 17 are also bored through the center of the slide plate 15.
The main plate 10 and the slide plate 15 are interconnected through the torsion spring 19. That is, an end of the torsion spring 19 is fitted into the fixing hole 12 of the main plate 10 while the other end of the torsion spring 19 is fitted into the fixing hole 17 of the slide plate 15. A pair of the torsion springs 19 are provided in a symmetric manner.
According to the related art slide type portable terminal, when the slide unit 5 is slid against the main unit 1, the slide plate 15 is slid along the main plate 10. At this time, the torsion spring 19 provides an elastic force such that the slide unit 5 can be kept in a state (i.e., closed) where it overlaps the main unit 1 and a state (i.e., open) where it fully protrudes beyond the main unit 1 (i.e., a state of FIG. 1). In other words, if a user moves the slide unit 5 to a certain position with respect to the main unit 1, the slide unit 5 will be moved toward a predetermined position by means of the elastic force of the torsion spring 19.
However, as described above, the related art slide type portable terminal has various problems and disadvantages. According to the related art, the slide unit 5 is slid against the main unit 1 up to a predetermined position using a force applied by the user and from the predetermined position using the elastic force of the torsion spring 19. In particular, the elastic force of the torsion spring 19 is used to allow the slide unit 5 to be positioned at both ends (i.e., open and closed states) of the stroke in which the slide unit 5 can be slid along the main unit 1. However, the torsion spring 19 is configured such that both ends thereof are fixed to the main plate 10 and the slide plate 15, respectively, while the other portions thereof can be freely moved. Therefore, there is a problem that since the elastic force of the torsion spring 19 is not always constant, the sliding operation of the slide unit 5 against the main unit 1 cannot be kept uniform.
Further, the elastic force of the torsion spring 19 cannot be exerted on the slide unit 5 until the slide unit 5 is slid further than a half of the stroke of the slide unit 5. Thus, the user should apply a force to the slide unit 5 for a relatively long distance for the slide unit 5 to be properly operated. Therefore, there is another problem in that the sliding operation of the slide unit 5 is relatively difficult.
Moreover, there is a problem in that the user cannot be clearly aware that the slide unit 5 has been completely opened or closed (i.e., that the slide unit 5 has been moved to opposite end locations). In other words, positions where the main unit 1 is fully opened and closed because of the sliding operation of the slide unit 5 are not clearly known by the user.
In addition, the main unit 1 can be either overlapped with or fully exposed to the outside because of the elastic force of the torsion spring 19. Therefore, there is a problem in that it is hard for the user to use the portable terminal in various modes.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.